The invention relates to an integrated optic device comprising a glass substrate, a flat, active, thin, guiding layer deposited on a surface of the substrate, and a zone in the form of a channel achieved in the substrate by ion exchange and comprising a first section, of predetermined cross section, flush with said surface and covered by the thin layer in such a way as to laterally bound a confinement zone of a light wave in the thin layer to form a monomode guide with lateral confinement by the substrate.
A known active optic device achieved in integrated optics comprises a polymer film deposited on a glass substrate and forming a guiding layer for the light. A non-guiding channel, formed by ion exchange in the substrate underneath the polymer film, defines a lateral confinement of the light waves in the part of the thin layer covering the channel. It has been proposed to use this type of optic device for optic switches (Article by N. E. SCHLOTTER et al.: "Fabrication of Channel waveguides in polydiacetylenes: composite diffused glass/polymer structures", AppI. Phys. Lett. 56(1), (Jan. 1, 1990).